Using a Star-Tree Index

In this recipe we’ll learn how to use the Star-tree index.

To understand how this recipe processes data, examine the commands executed in the Makefile.

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Makefile

Run this recipe using make.

make recipe

This will build up the infrastructure: Pinot and Kafka, create the tables, and produce streaming data.

Three tables will be generated:

• webtraffic - a real-time table with any Pinot indexes.
• webstraffic_inverted - a real-time table with an inverted index on the columns: country, browserType, and deviceBrand.

"invertedIndexColumns": [
  "country",
  "browserType",
  "deviceBrand"
],

• webtraffic_startree - a real-time table with a startree index.

"starTreeIndexConfigs": [
  {
    "dimensionsSplitOrder": [
      "country",
      "browserType",
      "deviceBrand"
    ],
    "skipStarNodeCreationForDimensions": [],
    "functionColumnPairs": [
      "COUNT__*",
      "SUM__timeSpent",
      "AVG__timeSpent"
    ],
    "maxLeafRecords": 10000
  }
],

Open your browser to the Pinot console and execute the SQL statements below.

select browserType, count(*)
from webtraffic 
WHERE country = 'Uruguay'
GROUP BY browserType
limit 10

select country, sum(timeSpent) AS totalTime
from webtraffic
group by country
order by totalTime DESC
limit 10

select count(*), sum(timeSpent) AS totalTime
from webtraffic
where country = 'United Kingdom'
order by totalTime DESC
limit 10

select browserType, count(*)
from webtraffic
WHERE country IN ('Germany', 'United Kingdom', 'Spain')
GROUP BY browserType
limit 10

Try changing FROM webtraffic to FROM webtraffic_inverted or FROM webtraffic_stree

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Clean up

make clean

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Troubleshooting

To clean up old Docker installations that may be interfering with your testing of this recipe, run the following command:

docker system prune